Research published in ACS Nano identifies a new type of sensor that could monitor body movement and advance the future of global health care. Although body motion sensors already exist in different forms, they have not been widely used due to their complexity and cost of production.
Graphene may be tough, but those who handle it had better be tender. The environment...
Researchers in Europe have succeeded for the first...
As hemp makes a comeback in the U.S. after a...
Researchers at the National Physical Laboratory in the U.K. have discovered that the conductivity at the edges of graphene devices is different to the central material. The group used local scanning electrical techniques to examine the local nanoscale electronic properties of epitaxial graphene, in particular the differences between the edges and central parts of graphene Hall bar devices.
Some of the most damaging brain diseases can be traced to irregular blood delivery in the brain. Now, Stanford Univ. chemists have employed lasers and carbon nanotubes to capture an unprecedented look at blood flowing through a living brain. The technique was developed for mice but could one day be applied to humans, potentially providing vital information in the study of stroke and migraines.
Graphene has excellent biocompatibility thanks to its great flexibility and chemical durability, and its conducting properties suggest uses for prosthetic devices in humans. Physicists are now developing key components of an artificial retina made of graphene. These retina implants may one day serve as optical prostheses for blind people whose optical nerves are still intact.
For the first time, researchers have succeeded in "growing" single-wall carbon nanotubes (CNT) with a single predefined structure, and hence with identical electronic properties. The method involved self-assembly of tailor-made organic precursor molecules on a platinum surface. In the future, carbon nanotubes of this kind may be used in ultra-sensitive light detectors and ultra-small transistors.
A group of scientists from South Korea have converted used-cigarette butts into a high-performing material that could be integrated into computers, handheld devices, electrical vehicles and wind turbines to store energy. In published research, the team has demonstrated that the cellulose acetate fibres that cigarette filters are mostly composed of could be transformed into a carbon-based material using pyrolysis.
Graphene has become a focus of research on a variety of potential uses. Now researchers at Massachusetts Institute of Technology have found a way to control how the material conducts electricity by using extremely short light pulses, which could enable its use as a broadband light detector.
Tough, ultra-light foam of atom-thick sheets can be made to any size and shape through a chemical process invented at Rice Univ. In microscopic images, the foam dubbed “GO-0.5BN” looks like a nanoscale building, with floors and walls that reinforce each other. The structure consists of a pair of 2-D materials: floors and walls of graphene oxide that self-assemble with the assistance of hexagonal boron nitride platelets.
A team of researchers has created a new way of manufacturing microstructured surfaces that have novel 3-D textures. These surfaces, made by self-assembly of carbon nanotubes, could exhibit a variety of useful properties—including controllable mechanical stiffness and strength, or the ability to repel water in a certain direction.
Scientists in the U.K. recently published work that describes how graphene can be wrapped around a silicon wire, or waveguide, and modify the transmission of light through it. These waveguide loops, called “racetrack resonators” because of their shape, could help form a device architecture that would make graphene biochemical sensors a reality.
Graphene, a material that consists of a lattice of carbon atoms, one atom thick, is widely touted as being the most electrically conductive material ever studied. However, not all graphene is the same. With so few atoms comprising the entirety of the material, the arrangement of each one has an impact on its overall function.
A new material structure developed at Massachusetts Institute of Technology generates steam by soaking up the sun. The structure—a layer of graphite flakes and an underlying carbon foam—is a porous, insulating material structure that floats on water. When sunlight hits the structure’s surface, it creates a hotspot in the graphite, drawing water up through the material’s pores, where it evaporates as steam.
Most current methods of identifying intracellular information result in the death of the individual cells, making it impossible to continue to gain information and assess change over time. Using magnetized carbon nanotubes, scientists in Texas have devised a new method for extracting molecules from live cells without disrupting cell development.
A team including scientists from Spain and from IBM Research in Switzerland have published work which describes an extremely simple method to obtain high quality nanographenes from easily available organic compounds. This method is based on the reactivity of a group of molecules named arynes, which can act as "molecular glue" to paste graphene fragments together.
Marilyn Minus, a materials expert and assistant professor at Northeastern Univ., is exploring directed self-assembly methods using carbon nanotubes and polymer solutions. So far, she’s used the approach to develop a polymer composite material that is stronger than Kevlar yet much lighter and less expensive. Minus is now expanding this work to incorporate more polymer classes: flame retardant materials and biological molecules.
Rutgers Univ. researchers have developed a technology that could overcome a major cost barrier to make clean-burning hydrogen fuel. The new catalyst is based on carbon nanotubes and may rival cost-prohibitive platinum for reactions that split water into hydrogen and oxygen.
The addition of elements to the surface of graphene can modify the material’s physical and chemical properties, potentially extending the range of possible applications. Recently performed theoretical calculations at RIKEN in Japan show that the addition of oxygen to graphene on copper substrates results in enhanced functionalization. The resulting structure, known as an enolate, make support applications that require catalytic response.
Using graphene ribbons just several atoms across, a group of researchers at the Univ. of Wisconsin-Milwaukee has found a novel way to “tune” the material, causing the extremely efficient conductor of electricity to act as a semiconductor. By imaging the ribbons with scanning-tunneling microscopy, researchers have confirmed how narrow the ribbon width must be. Achieving less than 10 nm in width is a big challenge.
Recent research at the Rice Univ. lab of materials scientist Pulickel Ajayan has discovered that nanotubes that hit a target end first turn into mostly ragged clumps of atoms. But nanotubes that happen to broadside the target unzip into handy ribbons that can be used in composite materials for strength and applications that take advantage of their desirable electrical properties.
Physicists in Europe have solved a mystery that has puzzled scientists for half a century. it has long been known that the distance between the graphene oxide layers depends on the humidity, not the actual amount of water added. But now, with the help of powerful microscopes, it can be seen how distance between graphite oxide layers gradually increases when water molecules are added, and why this phenomenon occurs.
Researchers in Germany have produced a new material the size of a sugar cube that has a surface area equivalent to more than seven tennis courts. This novel type of nanofiber has a highly ordered and porous structure gives it an extraordinarily high surface-to-volume ratio and could be a key enabling technology for lithium-sulfur batteries.
A group of researchers from Russia, Belarus and Spain, including MIPT professor Yury Lozovik, have developed a microscopic force sensor based on carbon nanotubes. The device consists of two nanotubes placed so that their open ends are opposite to each other. Voltage of just 10 nA is then applied to the nanocircuit and force is measured by the change in position of the nanotubes.
At the nanoscale, where objects are measured in billionths of meters and events transpire in trillionths of seconds, things do not always behave as our experiences with the macro world might lead us to expect. Water, for example, seems to flow much faster within carbon nanotubes than classical physics says should be possible. Now imagine trying to capture movies of these almost imperceptibly small nanoscale movements.
An international team has developed an elegant method for producing self-organized and functionalized carbon nanolayers and equipping them chemically with a range of functions. The effort depended on the development of a special compound, the molecules of which were aligned perfectly in parallel to each other in a single self-organized layer, like the bristles on a brush.
The electrons in graphene behave as “massless” particles, yet these electrons also seem to have dual personalities. Phenomena observed in the field of graphene plasmonics suggest that when the electrons move collectively, they must exhibit mass. After two years of effort, researchers at Harvard Univ. have successfully measured the collective mass of “massless” electrons in motion in graphene.
According to researchers, a simple, scalable method of making strong, stretchable graphene oxide fibers that are easily scrolled into yarns and have strengths approaching that of Kevlar is possible. An international collaboration has recently produced graphene oxide yarn fibers much stronger than other carbon fibers.
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